The Effects of Birth Order on Personality Traits and Feelings of Academic Sibling Rivalry Julia Badger & Peter Reddy
Total Page:16
File Type:pdf, Size:1020Kb
The effects of birth order on personality traits and feelings of academic sibling rivalry Julia Badger & Peter Reddy Abstract The influence of birth order on personality and sibling rivalry is controversial; little research has been con- ducted into academic sibling rivalry, and none into the connection with personality traits. This study con- siders the interaction of all three factors. Firstborns (N=22) and lastborns (N=24) completed online personality tests and an Academic Sibling Rivalry Questionnaire. Lastborns were found to experience more academic sibling rivalry: t=2.33, DF=44; p<.05, whereas firstborns are more likely to be conscientious: F(1,44)=3.58; p< .05, and dutiful: F(1,44)=5.39; p<.05. This raises possible implications in domains including education, health and psychotherapy. Further research could be conducted to expand these find- ings in terms of variables and geographical location. N THE GALAPAGOS ISLANDS Charles each other for not only survival, but also Darwin (1859) found 13 variations of parental favour. Sibling rivalry can be Ifinch and concluded that these variations described as ‘the jealousy, competition and had emerged as the most suitable for that fighting between brothers and sisters’ (Uni- time and that environment through natural versity of Michigan Health System, 2007. selection. Darwin proposed that the ‘fittest’ pp1) and is common when there is more variations within a species were the most than one sibling in a family (Johnson, 1998). likely to survive and reproduce and therefore Trivers (1974) points out that every child ini- more likely to pass on their genetic traits; the tially sees himself as more important than his ‘survival of the fittest’. Darwin believed that it siblings (twice as valuable) and needs to be was survival of the fittest that resulted in off- taught to share and be kind. spring (sibling) rivalry. Rivalry can certainly There are of course instances in other be found within a plethora of biological con- biological kinds whereby siblings support, texts, for example the first Indian Black Plum rather than fight against each other for the tree ovule releases a ‘death chemical’ to benefit of the species: Trivers (1985) starve and kill other Black Plum ovules described how Taiwanese aphids work (Krishnamurthy, Shaanker & Ganeshaiah, together; the firstborn will become the ‘sol- 1997); the first African Black eagle chick to dier’ and protect the second-born who will hatch pecks the other chick to death (Mock, become the ‘reproductive’ caste. Hamilton Drummond & Stinson, 1990; Mock & Parker, (1964) suggests that altruism may be a result 1998); 25 per cent of Spotted Hyena off- of natural selection by re-focusing on the spring succumb to sibling aggression, increas- genetic rather than the individual level: ing to 50 per cent within same-sex litters interest is in the gene pool if it enables more (Hamilton, 1967). Hamilton (1964; Trivers, individuals to survive (inclusive fitness as 1974) suggests that sibling rivalry is a means opposed to survival of the fittest). of competing for scarce resources – as long as the benefits are greater than twice the cost. Sibling rivalry amongst humans Thus natural selection includes the biological The scale of influence of evolutionary factors disposition of offspring to compete against on human behaviour relative to culture and Psychology Teaching Review Vol 15 No 1 45 © The British Psychological Society 2009 Julia Badger and Peter Reddy social construction is open to debate; clearly Birth order and personality influences social or environmental factors play a part. Sibling rivalry has been well documented Sulloway (2001; p40) discusses ultimate and with connection to birth order and personal- proximate influences on sibling behaviour: ity, however there are still outstanding con- ultimate causes of behaviour are ‘adaptive troversies (with few consistent findings; tendencies that have evolved by natural Schooler, 1972) over the types of rivalry selection’, and encompass Darwin’s theory investigated. Adler (1927; Leman, 1985) of natural selection and the biological dispo- remarked that birth order is a great contrib- sition to compete for parental focus and utor to why children of the same family, with attention to survive childhood, whereas similar genes, end up with very different per- proximate causes of behaviour are due to sonalities. Adler claimed that the firstborn ‘influences operating during the life- child experiences the ‘only child life’ and is time…biological as well as environmental centre of attention until the second-born factors, which almost always interact with child arrives, which can cause anger and one another’. These influences include vary- frustration. If the situation is handled appro- ing environmental situations that the indi- priately, the firstborn child could develop vidual must react to, to successfully proceed into a responsible, protective person. How- through life and survive natural selection. ever, in extreme cases when the situation is For example, bird migration is an ultimate handled inappropriately, the firstborn can adaptation based on natural selection, how- become neurotic and criminal. Adler char- ever, the immediate triggers for migration – acterises lastborns as ambitious but spoilt: the proximate causes – may include temper- this child is constantly trying to catch-up with ature and length of daylight (Mayr, 1961). or surpass the eldest child but is more likely Therefore, the cause of human sibling to become a neurotic problem child. Sul- rivalry may ultimately be traced back to nat- loway (2001; 1996) claims that firstborns ural selection (Sulloway’s ultimate influ- seek parental approval by taking on the role ence), however, the way in which an of surrogate parent to their sibling (leading individual conducts their rivalry depends on to conscientiousness), whereas laterborns, immediate, or proximate environmental, unable to take on this surrogate role, social and situational factors (Sulloway’s develop new talents and seek new interests proximate influence). and activities within the family in order to Siegler (2007) notes a variety of possible prove that they are worthy of attention (lead- non-biological influences on human sibling ing to openness to experience). Roach rivalry: parental conflict; parental favourites – (1997) replicated Sulloway’s work cross-cul- this can increase the rivalry from the ‘less- turally, among several hundred horticultur- loved’ child and can cause guilt in the ‘loved’ alist Shuar Indians, and found nearly child, and children being encouraged to take identical correlations between birth order on the same hobbies and interests. Lamb and and personality traits. Sulloway (2001) Sutton-Smith (1982) suggest two main types claimed evidence that firstborns are more of sibling rivalry influence: adult-initiated likely to be more conscientious and socially and sibling-generated. Adult-initiated can be dominant, but less agreeable and open to split into two categories: overt and covert. new experiences than laterborns. He also Overt adult-initiated rivalry includes state- notes different competitive strategies ments of comparison between two siblings. between firstborns and laterborns: firstborns Covert comparisons would include subtle – being generally bigger – tend to use more statements without the direct comparison. physical dominance and intimidation, Sibling-generated rivalry attempts to gain whereas laterborns tend to use techniques of parental attention and increase status within whining, humour and social intelligence. the sibling relationship. Zajonc and Mullally (1997; Zajonc, 2001; 46 Psychology Teaching Review Vol 15 No 1 The effects of birth disorder on personality traits and feelings of academic sibling rivalry Downey, 2001) found that firstborns had a with various sub-questions, asking about more intellectually stimulating environment rivalry at different age ranges and in the than laterborns – the confluence model – three domains. They found that 56 per cent which, influenced the likelihood of differing of individuals had experienced the most sib- personality traits between firstborns and lat- ling rivalry between the ages of 10-15 years, erborns. Zajonc and Mullally commented and the greatest rivalry (38 per cent) had that firstborns experience the ‘tutor effect’ occurred within an academic setting. They (teaching their younger siblings) and their also found that students aged 20-25 rated intelligence benefits from this. Retherford academic sibling rivalry very high: 65 per and Sewell (1991) carried out developmen- cent, with social sibling rivalry at about 30 tal and cross-cultural studies testing this per cent. Between the ages of 20-25, an indi- notion, and found supporting evidence with vidual at college or university has many aca- controlled samples. demic pressures as they strive for Other issues have been noted about gen- achievement and status. When individuals der and age potentially creating, enhancing reach this stage in their education, academic or reducing rivalry. Rimm (2002) suggested rivalry is no longer just about parental that the closer in age two same-sex siblings favour, but also includes competition for are, the more likely it is that there will be respect, status and job prospects: achieving a competition between them and suggests that higher degree is not just seen as a sense of this is because they are expected to like the academic accomplishment, but as a means of same things, act in the same way and achieve securing a higher